Method of inhibiting neurotrophin-receptor binding

ABSTRACT

The present invention relates to compositions which inhibit the binding of nerve growth factor to the p75 NTR  common neurotrophin receptor and methods of use thereof. In one embodiment, the compound which inhibits binding of nerve growth factor to p75 NTR  comprises, particularly when bound to nerve growth factor, at least two of the following: (1) a first electronegative atom or functional group positioned to interact with Lys 34  of nerve growth factor; (2) a second electronegative atom or functional group positioned to interact with Lys 95  of nerve growth factor; (3) a third electronegative atom or functional group positioned to interact with Lys 88  of nerve growth factor; (4) a fourth electronegative atom or functional group positioned to interact with Lys 32  of nerve growth factor; and (5) a hydrophobic moiety which interacts with the hydrophobic region formed by Ile 31 , Phe 101  and Phe 86  of nerve growth factor.

RELATED APPLICATION

This application is a continuation of U.S. Ser. No. 09/310,883, filedMay 17, 1999, the entire teachings of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

The neurotrophins are a family of structurally and functionally relatedproteins, including Nerve Growth Factor (NGF), Brain-DerivedNeurotrophic Factor (BDNT), Neurotrophin-3 (NT-3), Neurotrophin-4/5(NT-4/5) and Neurotrophin-6 (NT-6). These proteins promote the survivaland differentiation of diverse neuronal populations in both theperipheral and central nervous systems (Hefti, 1986; Hefti and Weiner,1986; Levi-Montalcini, 1987; Barde, 1989; Leibrock et al., 1989;Maisonpierre et al. 1990; Rosenthal et al., 1990; Hohn et al., 1990;Gotz et al., 1994; Maness et al., 1994) and are involved in thepathogenesis of diverse neurological disorders. Neurotrophins exert manyof their biological effects through specific interactions with a classof transmembrane receptor tyrosine kinases (trkA, trkB and trkC) (Kaplanet al., 1991; Klein et al. 1991, 1992; Soppet et al., 1991; Squinto etal., 1991; Berkemeier et al., 1991; Escandon et al., 1993; Lamballe etal., 1991). Specificity of neurotrophin action results from theirselective interactions with the trk receptors. That is, trkA only bindsNGF (Kaplan et al., 1991; Klein et al. 1991); trkB binds BDNF and NT-4/5(Soppet et al., 1991; Squinto et al., 1991; Berkemeier et al., 1991;Escandon et al., 1993; Lamballe et al., 1991; Klein et al., 1992; Valeand Shooter, 1985; Barbacid, 1993); and trkC exclusively binds NT-3(Lamballe et al., 1991; Vale and Shooter, 1985). This is particularlyevident when the trk receptors are coexpressed with the commonneurotrophin receptor p75^(NTR) (For review see Meakin and Shooter, 199;Barbacid, 1993; Chao, 1994; Bradshaw et al., 1994; Ibáñez, 1995).

The common neurotrophin receptor p75^(NTR) is a transmembraneglycoprotein structurally related to the tumor necrosis factor and CD-40receptors (Meakin and Shooter, 1992; Rydén and Ibáñez, 1996). As allneurotrophins bind to p75^(NTR) with similar affinity (Rodrizuez-Tébaret al. 1990; Hallböök et al., 1991; Rodriguez-Tébar et al., 1992;Ibáñez, 1995), neurotrophin specificity is conventionally thought to becaused by the binding selectivity for trk receptors which aredifferentially expressed in different neuronal populations (Ibáñez,1995). However, accumulated experimental data on neurotrophin activityreveal important functional aspects of p75^(NTR) (Heldin et al., 1989;Jing et al. 1992; Herrmann, 1993; Barker and Shooter, 1994; Dobrowsky etal. 1994, Matsumoto et al. 1995; Marchetti et al., 1996; Washiyama etal., 1996). The common neurotrophin receptor enhances functions andincreases binding specificity of trk receptors (Barker and Shooter,1994; Mahadeo et al., 1994; Chao and Hempstead, 1995; Rydén and Ibáñez,1996). In addition, p75^(NTR) possesses unique, trk-independentsignaling properties which involve ceramide production throughactivation of the sphingomyelin cycle (Dobrowsky, et al. 1994),apoptosis (cell death) (Van der Zee et al. 1996; Cassacia-Bonnefil etal., 1996; Frade et al. 1996), and activation of the transcriptionfactor NFκB (Carter et al., 1996). Recently, p75^(NTR) has beendemonstrated to participate in human melanoma progression (Herrmann etal. 1993; Marchetti et al., 1996). Furthermore. NGF and NT-3 increasethe production of heparin by 70 W melanoma cells, which is associatedwith their metastatic potential (Marchetti et al., 1996). Although thiseffect has been shown to be mediated by the common neurotrophinreceptor, neither BDNF nor NT-4/5 appeared to be active.

Due to the implication of NGF/p75^(NTR) binding in various diseasestates, a need exists for pharmaceutical agents and methods of usethereof for interfering with the binding of NGF to the p75^(NTR) commonneurotrophin receptor.

SUMMARY OF THE INVENTION

The present invention relates to the discovery of molecular structuralfeatures which contribute to the ability of a compound to inhibit thebinding of NGF to the common neurotrophin receptor p75^(NTR). Compoundswhich have these features are of use, for example, for inhibitingbinding of NGF to p75^(NTR). Such compounds can also be used to treat apatient having a condition which is mediated, at least in part, by thebinding of NGF to p75^(NTR).

In one embodiment, the present invention relates to compositions whichinhibit the binding of nerve growth factor to the p75^(NTR) commonneurotrophin receptor and methods of use thereof.

In one embodiment, the compound which inhibits binding of nerve growthfactor to p75^(NTR) comprises at least two of the following: (1) a firstelectronegative atom or functional group positioned to interact withLys³⁴ of nerve or growth factor; (2) a second electronegative atom orfunctional group positioned to interact with Lys⁹⁵ of nerve growthfactor; (3) a third electronegative atom or functional group positionedto interact with Lys⁸⁸ of nerve growth factor; (4) a fourthelectronegative atom or functional group positioned to interact withLys³² of nerve growth factor; and (5) a hydrophobic moiety whichinteracts with the hydrophobic region formed by amino acid residues ofnerve growth factor, including Ile³¹, Phe¹⁰¹ and Phe⁸⁶. Such inhibitors,preferably, bind nerve growth factor via at least two of the foregoinginteractions.

In one embodiment, compounds which inhibit binding of nerve growthfactor to p75^(NTR) have Formula 1,

In Formula 1. D₁, D₂, E₁, E₂ and G are each, independently, ansp²-hybridized carbon or nitrogen atom. One of X₁ and X₂ is a hydrogenatom or absent, while the other is an electronegative atom or anelectronegative functional group. R and R₂ are each, independently, anelectronegative atom or an electronegative functional group, such as O,S, CH₂, or NR³, where R₃ is H, alkyl, preferably C₁-C₆-alkyl, or aryl,such as phenyl. R, R₂ and one of X₁ and X₂ can also each be,independently, an electronegative atom or functional group, such asalkylcarbonyl; alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH;—CN; —CO₂H; —SO₃H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H,—OC(O)(OH); halomethyl, dihalomethyl or trihalomethyl group or afluorine, chlorine, bromine or iodine atom. Y is N, O, S, C-L or N-L,where L is H, alkyl, preferably C₁-C₆-alkyl, or an electronegative atomor functional group, such as, but not limited to, alkylcarbonyl;alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH; —CN; —CO₂H;—SO₃H; —SO₂H; —PO₃H; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H, —OC(O)(OH);halomethyl, dihalomethyl or trihalomethyl groups or a halogen atom, suchas a fluorine, chlorine, bromine or iodine atom. Z and Z₁ are each,independently, O, S, CH, C(O), N, NH, N-alkyl, N-cycloalkyl and N—P,where P is a carbohydrate moiety, such as a monosaccharide group, forexample, a fucosyl, glucosyl, galactosyl, mannosyl, fructosyl, gulosyl,idosyl, talosyl, allosyl, altrosyl, ribosyl, arabinosl, xylosyl orlyxosyl group. T₁ and T₂ are each, independently, an sp²- orsp³-hybridized carbon or nitrogen atom. a, b, and c are each 0 or 1,provided that at least one of b and c is 1. R₁ is a monocyclic orpolycyclic aryl or heteroaryl, monosaccharide or oligosaccharide, alkyl,cycloalkyl, arylalkyl, alkylamino or alkoxy group which is substitutedwith at least one substituent selected from the group consisting ofelectronegative atoms and electronegative functional groups.

It will be appreciated that in this and the following structures, thelines connecting the variables can be single or double bonds. Inaddition, hydrogen atoms are added to the variables as necessary tocomplete the valence of the atom.

In another embodiment, compounds have Formula 3,

In another embodiment, the NGF/p75^(NTR) binding inhibitor has Formula 3

where D₁, D₂, X₁, X₂, Y, E₁, E₂, T₁, T₂, R, G, R₁, R₂, and c have themeanings given above for these variables in Formula 1. Y₁, Y₂, and Y₃are independently selected from the identities given for Y in Formula 1.E₃ and E₄ are each, independently, an sp²-hybridized carbon or nitrogenatom, and d and h are, independently, 0 or 1.

In another embodiment, compounds which inhibit the binding of nervegrowth factor to p75^(NTR) have Formula 2,

In Formula 2, D₁, D₂, E₁, E₂, E₃, E₄ and G are each, independently, ansp²-hybridized carbon or nitrogen atom. One of X₁ and X₂ is a hydrogenatom or absent, while the other is an electronegative atom or anelectronegative functional group. R, R₂ and R₄ are each, independently,an electronegative atom or an electronegative functional group, such asO, S, CH₂, or NR₃, where R₃ is H, OH, alkyl, preferably C₁-C₆-alkyl, oraryl, such as phenyl. R, R₂ and one of X₁ and X₂ can also each be,independently, an electronegative atom or functional group, such asalkylcarbonyl; alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH;—CN; —CO₂H; —SO₃H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H,—OC(O)(OH); halomethyl, dihalomethyl or trihalomethyl group or afluorine, chlorine, bromine or iodine atom. Y is N, O, S, C-L or N-L,where L is H, alkyl preferably C₁-C₆-alkyl, or an electronegative atomor functional group, such as, but not limited to, alkylcarbonyl;alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH; —CN; —CO₂H;—SO₃H; —SO₂H; —PO₃H; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H, —OC(O)(OH);halomethyl, dihalomethyl or trihalomethyl groups or a halogen atom, suchas a fluorine, chlorine, bromine or iodine atom. Z and Z₁ are each,independently, O, S, CH, C(O), N, NH, N-alkyl, N-cycloalkyl and N—P,where P is a carbohydrate moiety, such as a monosaccharide group, forexample, a fucosyl, glucosyl, galactosyl, mannosyl, fructosyl, gulosyl,idosyl, talosyl, allosyl, altrosyl, ribosyl, arabinosyl, xylosyl orlyxosyl group. T₁, T₂ and T₃ are each, independently, an sp²- orsp³-hybridized carbon or nitrogen atom. When f is 0, T₃ can further havethe meanings given for Z and Z₁, above a, b, c, d, e, f, g, h and i areeach 0 or 1, provided that at least one of b and c is 1, at least one ofd and e is 1 and at least one of f and i is 1. R₁ is a monocyclic orpolycyclic aryl or heteroaryl, monosaccharide or oligosaccharide, alkyl,cycloalkyl, arylalkyl, alkylamine or alkoxy group which is substitutedwith at least one substituent selected from the group consisting ofelectronegative atoms and electronegative functional groups.

In another embodiment, a compound which inhibits the binding of NGF top75^(NTR) has Formula 5,

wherein D₁, D₂, X₁, X₂, E₁, E₂, E₃, T₁, T₂, T₃, Z, G, R₁, R₂, R₄, b, e,f, i, and c have the meanings given for these variables in Formula 2,Y₁, Y₂, and Y₃ are independently selected from the identities given forY in Formula 2, and h is 0 or 1. E₅ and E₆ are each, independently, ansp²-hybridized carbon or nitrogen atom, and g is 0 or 1. Ring 4 can befurther unsubstituted or substituted with one or more substituents, suchas alkyl or aryl groups.

In another embodiment, the invention provides a pharmaceuticalcomposition comprising at least one compound of the invention, orpharmaceutically acceptable salt thereof, in combination with apharmaceutically acceptable carrier or excipient.

The invention also provides a method of inhibiting the binding of nervegrowth factor to the p75^(NTR) receptor. The method comprises contactingcells which express the p75^(NTR) receptor with a nerve growthfactor/p75^(NTR) binding inhibitor of the invention in an amount whichis sufficient to inhibit binding of nerve growth factor to the p75^(NTR)receptor. The method can be practiced in vivo or in vitro.

In another embodiment, the invention relates to a method of treating acondition in a patient which is mediated by the binding of nerve growthfactor to the p75^(NTR) receptor. The method comprises administering tothe patient a therapeutically effective amount of a nerve growthfactor/p75^(NTR) binding inhibitor of the invention. Preferably, thecompound to be administered selectively inhibits the binding of nervegrowth factor to p75^(NTR) in cells which do not express the NGFreceptor trkA.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates examples of suitable configurations forelectronegative atoms in the NGF/p75^(NTR) binding inhibitors of theinvention.

FIG. 2 illustrates examples of electronegative functional groups.

FIG. 3 sets forth a synthetic pathway for certain compounds of theinvention: Pg=protecting group.

FIG. 4 sets forth a synthetic pathway for certain compounds of theinvention.

FIG. 5 sets forth a synthetic pathway for certain compounds of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

Nerve growth factor (also referred to hereinafter as “NGF”) is aneurotrophin implicated in the pathogenesis of Alzheimer's disease,epilepsy and pain (Ben and Represa, 1990; McKee et al. 1991; Leven andMendel, 1993; Woolf and Doubell, 1994; Rashid et al. 1995; McMahon etal., 1995). The binding of NGF to its receptors is determined bydistinct sequences within its primary, amino acid structure. Whileseveral regions of NGF participate in the NGF/trkA interaction, mutationstudies suggest that relatively few key residues, namely those locatedin the NGF amino and carboxyl termini, are required for high affinitybinding.

NGF displays high and low affinity binding sites in sensor, andsympathetic neurons and in pheochromocytoma PC12 cells (Sutter et al.,1979; Landreth and Shooter, 1980; Schechter and Bothwell, 1981). Thecoexpression of the common neurotrophin p75^(NTR) receptor with trkA isrequired to form the high affinity binding site (Hempstead et al., 1991;Barker and Shooter, 1994; Mahadeo et al., 1994; Chao and Hempstead,1995). Several models of the trkA-p75^(NTR) interaction have beenproposed to explain high affinity NGF binding (Bothwell, 1991; Chao,1992b; Chao and Hempstead, 1995; Wolf et al., 1995; Ross et al., 1996;Ross et al., 1997). These models differ with respect to direct(conformational model) or indirect (ligand-presentation model)interaction of p75^(NTR) with trkA. Direct trkA-p75^(NTR) interaction isconsistent with much of the existing experimental data.

The hairpin loop at residues 29-35 of NGF is responsible for recognitionby p75^(NTR) (Ibáñez et al., 1992; Radziejewski et al. 1992), while theamino and carboxyl termini are important binding determinants forrecognition by the trkA receptor (Shih et al., 1994; Moore and Shooter,1975: Suter et al., 1992; Burton et al., 1992; Kahle et al., 1992; Luoand Neet, 1992; Drinkwater et al., 1993; Treanor et al., 1995; Taylor etal. 1991; Shamovsky et al., 1998; Shamovsky et al., 1999; WO 98/06048).Truncation of either the amino or carboxyl terminus of NGF produces lessactive NGF analogues; similarly most deletion or point mutations of theamino terminus also lead to NGF analogues with diminished activity (Shihet al., 1994; Burton et al., 1992, 1995; Kahle et al., 1992; Drinkwateret al., 1993; Treanor et al., 1995; Taylor et al., 1991). On the otherhand, the NGFΔ2-8 (NGF with residues 2-8 removed) and NGFΔ3-9 deletionmutants are almost as active as wild type NGF (Drinkwater et al., 1993).These NGF structure-activity relationships in combination with theconsiderable species variability (mouse, human, guinea pig and snake) ofthe amino acid sequence of the NGF termini (McDonald et al., 1991) areof potential value in understanding the NGF/trkA interaction.

NGF exerts its biological activity as a non-covalent dimer (Treanor etal., 1995; Burton et al., 1995; McDonald et al., 1991; Ibáñez et al.,1993; Bothwell and Shooter, 1977). Two 118 residue NGF monomers aredimerized by hydrophobic and van der Waals interactions between theirthree anti-parallel pairs of β-strands; consequently, the amino terminusof one NGF monomer and the carboxyl terminus of the other are spatiallyjuxtaposed (McDonald et al., 1991). Furthermore, although a dimer has 2pairs of termini, only one pair of termini is required for trkA receptorrecognition (Treanor et al., 1995; Burton et al., 1995).

The X-ray crystallographic 3-dimensional structure of a dimeric mouseNGF (mNGF) has been reported (McDonald et al., 1991). However, withinthis structure, the amino terminus (residues 1-11) and the carboxylterminus (residues 112-118) remain unresolved for both pairs of termini.High flexibility of the NGF termini makes it difficult to experimentallydetermine their bioactive conformations, particularly since transitionmetal ions commonly used in X-ray crystallography (McDonald et al.,1991) have high affinity for His residues (Gregory et al., 1993) whichare present in the NGF amino terminus (Bradshaw et al. 1994). Indeed,conformational alterations in the receptor binding domains of NGF causedby Zn²⁺ cations leading to its inactivation have been described recently(Ross et al., 1997). Since the amino and carboxyl termini are crucialfor NGF bioactivity as mediated via trkA and because of the significanceof NGF in multiple neurologic disease processes, the determination ofthe biologically active conformation of these termini is an importantand challenging problem for computational chemistry.

The present invention relates to the discovery of molecular structuralfeatures which contribute to the ability of a compound to inhibit thebinding of NGF to the common neurotrophin receptor p75^(NTR). Compoundswhich have these features are of use, for example, for inhibitingbinding of NGF to p75^(NTR) Such compounds can also be used to treat apatient having a condition which is mediated, at least in part, by thebinding of NGF to p75^(NTR).

Certain compounds which inhibit the binding of NGF to p75^(NTR) aredisclosed in copending U.S. patent application Ser. No. 09/292,450,incorporated herein by reference in its entirety.

In one embodiment, the present invention provides compounds whichinhibit the binding of nerve growth factor (NGF) to the p75^(NTR)receptor. The compounds have at least two of the followingcharacteristics: (1) a first electronegative atom or functional grouppositioned to interact with Lys³⁴ of NGF; (2) a second electronegativeatom or functional group positioned to interact with Lys⁹⁵ of NGF; (3) athird electronegative atom positioned to interact with Lys⁸⁸ of NGF; (4)a fourth electronegative atom or functional group positioned to interactwith Lys³² of NGF; and (5) a hydrophobic moiety which interacts with thehydrophobic region formed by Ile³¹, Phe¹⁰¹ and Phe⁸⁶ of NGF. A compoundhaving two or more of these structural attributes is referred to hereinas an “NGF/p75^(NTR) binding inhibitor”. Preferably, the NGF/p75^(NTR)binding inhibitor has at least three of the foregoing attributes whenbound to NGF, more preferably at least four such attributes. Mostpreferably, the NGF/p75^(NTR) binding inhibitor has each of the fiveforegoing attributes. Typically, an NGF/p75^(NTR) binding inhibitor ofthe invention interacts with NGF via at least two of the foregoinginteractions when bound to NGF.

The term “electronegative atom”, as used herein, refers to an atom whichcarries a partial or full negative charge in a particular compound underphysiological conditions. The electronegative atom can be, for example,an oxygen atom, a nitrogen atom, a sulfur atom or a halogen atom, suchas a fluorine, chlorine, bromine or iodine atom. Preferably theelectronegative atom is an oxygen atom. The term “electronegativefunctional group”, as used herein, refers to a functional Croup whichincludes at least one electronegative atom. Electronegative groupsinclude acid functional groups and other polar functional groups. Forexample, suitable electronegative functional groups include, but are notlimited to, carbonyl, thiocarbonyl, ester, imino, amido carboxylic acid,sulfonic acid, sulfinic acid, sulfamic acid, phosphonic acid, boronicacid, sulfate ester, hydroxyl, mercapto, cyano, cyanate, thiocyanate,isocyanate, isothiocyanate, carbonate, nitrate and nitro groups. It isto be understood that, unless otherwise indicated, reference herein toan acidic functional group also encompasses salts of that functionalgroup in combination with a suitable cation.

An electronegative atom of the NGF/p75^(NTR) binding inhibitor bears afull or partial negative charge under physiological conditions and can,therefore, interact electrostatically with the positively charged sidechain of an NGF lysine residue. This will be an interaction, such as,for example, a hydrogen bond, an ion/ion interaction, an ion/dipoleinteraction or a dipole/dipole interaction. The hydrophobic region ormoiety of the NGF/p75^(NTR) binding inhibitor can interact with ahydrophobic region of NGF via a hydrophobic interaction. Without beingbound by theory, it is believed that compounds having the disclosedstructural features can interact with NGF in such a way as to interferewith, and thereby inhibit, the binding of NGF to p75^(NTR).

The ability of a compound to interact with the amino acid residues ofNGF specified above can be determined using a structural model of NGFobtained using a energy-minimization algorithm, as described inpublished PCT application WO 98/06048, incorporated herein by referencein its entirety. For example, a molecule will interact with thespecified residues of NGF, as discussed above, if it has at least 3electronegative atoms (A, B and C) such that at least one of thefollowing two conditions is satisfied: (i) atoms A and B are separatedby 5-7 covalent bonds, B and C are separated by 6-8 covalent bonds, andA and C are separated by 10-14 covalent bonds and (ii) distance betweenA and B is between 4.5 and 7.5 angstroms, and distance between B and Cis between 4.5 and 7.5 angstroms. The number of covalent bondsseparating atoms can be determined from the structural formula of amolecule. Distance between atoms can be determined experimentally (e.g.,by X-ray crystallography, or NMR spectroscopy) or evaluatedtheoretically using any molecular builder (e.g. SYBYL from Tripos Inc.(St. Louis, Mo., USA) or QUANTA from Molecular Simulations Inc. (SanDiego, Calif., USA) as well as any molecular modeling technique (e.g.AMBER from Oxford Molecular Group Inc./University of California. SanFrancisco or CHARMm from Molecular Simulations Inc.) or quantum chemicaltechnique (e.g., MNDO from Oxford Molecular Group Inc. (Campbell,Calif., USA) University of Zurich; AMPAC from Semichem (Kansas City,Mo., USA); CADPAC from Oxford Molecular Group Inc./Cambridge University;Gaussian-98 from Gaussian Inc. (Carnegie, Pa., USA); or GAMESS from IowaState University). Examples of suitable configurations of groups A, Band C are illustrated in FIG. 1, while a representative group ofelectronegative functional groups is shown in FIG. 2.

Preferred NGF/p75^(NTR) inhibitors of the invention comprise a molecularscaffold or framework, to which the electronegative atoms or functionalgroups are attached, either directly or via an intervening moiety. Thescaffold can be, for example, a cyclic or polycyclic moiety, such as amonocyclic, bicyclic or tricyclic moiety, and can include one or morehydrocarbyl or heterocyclic rings. Preferably, the scaffold includes twoor more fused, planar, five- or six-membered rings. The molecularscaffold presents the attached electronegative atoms, electronegativefunctional groups or a combination thereof, in the proper configurationor orientation for interaction with the appropriate residues of NGF. Inaddition, the molecular scaffold, such as polycyclic system, or aportion thereof, can serve as the hydrophobic group which interacts withhydrophobic residues of NGF, as described above.

In one embodiment, the NGF/p75^(NTR) inhibitor is of general Formula 1,

In Formula 1, D₁, D₂, E₁, E₂ and G are each, independently, ansp²-hybridized carbon or nitrogen atom. One of X₁ and X₂ is a hydrogenatom or absent, while the other is an electronegative atom or anelectronegative functional group. R and R₂ are each, independently, anelectronegative atom or an electronegative functional group, such as O,S, CH₂, or NR₃, where R₃ is H, alkyl, preferably C₁-C₆-alkyl, or aryl,such as phenyl. R, R₂ and one of X₁ and X₂ can also each be,independently, an electronegative atom or functional group, such asalkylcarbonyl; alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH;—CN; —CO₂H; —SO₃H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H,—OC(O)(OH); halomethyl, dihalomethyl or trihalomethyl group or afluorine, chlorine, bromine or iodine atom. Y is N, O, S, C-L or N-L,where L is H, alkyl, preferably C₁-C₆-alkyl, or an electronegative atomor functional group, such as, but not limited to, alkylcarbonyl;alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH; —CN; —CO₂H;—SO₃H; —SO₃H; —PO₃H₂; —NO₂, —ONO₂, —CNO, —SH, —CNS, —OSO₃H, —OC(O)(OH);halomethyl, dihalomethyl or trihalomethyl groups or a halogen atom, suchas a fluorine, chlorine, bromine or iodine atom. Z and Z₁ are each,independently, O, S, CH, C(O), N, NH, N-alkyl, N-cycloalkyl and N—P,where P is a carbohydrate moiety, such as a monosaccharide group, forexample, a fucosyl, glucosyl, galactosyl, mannosyl, fructosyl, gulosyl,idosyl, talosyl, allosyl, altrosyl, ribosyl, arabinosyl, xylosyl orlyxosyl group. T₁ and T₂ are each, independently, an sp²- orsp³-hybridized carbon or nitrogen atom. a, b and c are each 0 or 1,provided that at least one of b and c is 1.

R₁ is a monocyclic or polycyclic aryl or heteroaryl, mono- oroligosaccharide, alkyl, cycloalkyl, arylalkyl, alkylamino or alkoxygroup which is substituted with at least one substituent selected fromthe group consisting of electronegative atoms and electronegativefunctional groups. Preferred monosaccharide groups include fucosyl,glucosyl, galactosyl, mannosyl, fructosyl, gulosyl idosyl, talosyl,allosyl, altrosyl, ribosyl, arabinosyl, xylosyl and lyxosyl groups. Theelectronegative substituent can be bonded to the aryl or heteroaryl ringsystem alkyl, cycloalkyl, or oligo- or monosaccharide group eitherdirectly or indirectly via a bridging group, for example, an alkylenegroup such as a C₁-C₄-alkylene group or an oxyalkylene group. Suitabledirectly bonded and alkylene bridged electronegative atoms andfunctional groups include, but are not limited to, alkylcarbonyl;alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH; —CN; —CO₂H;—SO₃H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H; —OC(O)(OH):carboxyalkyl, nitroalkyl, —N,N-dialkylaminosulfonyl, aminocarbonyl,alkoxycarbonyl, alkoxycarbonylalkyl, cyanocarbonylalkyl, haloalkyl, suchas fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl,dichloromethyl or trichloromethyl; alkylamido or a halogen atom, such asa fluorine, chlorine, bromine or iodine atom. In one embodiment, R₁ isselected from the group consisting of groups including, but not limitedto, —(CH₂)_(a)COOH; —(CH₂)_(a)NO₂; —(CH₂)_(a)OH; —(CH₂)_(a)PO₃H₂;—(CH₂)_(a)SO₃H; —(CH₂)_(a)SO₂H; —R₄(CH₂)_(a)COOH; —R₄(CH₂)_(a)NO;—R₄(CH₂)_(a)PO₃H₂; —R₄(CH₂)_(a)SO₂H; —R₄(CH₂)_(a)SO₃H; and—R₄(CH₂)_(a)OH, where a is 1 to 12, preferably 1 to about 4, and R₄ isNH or O.

Rings 1 and 2 are each, independently, a five- or six-membered ring and,preferably, are both planar.

It, is to be understood that compounds of Formula 1 and Formulas 2, 3and 5, below, will further include double bonds between adjacent atomsas required to satisfy the valence of each atom. That is, double bondsare added to provide the following number of total bonds to each of thefollowing types of atoms: carbon: four bonds; nitrogen: 3 bonds; oxygen:two bonds; and sulfur: two bonds.

The term “alkyl”, as used herein, refers to a normal, branched or cyclicaliphatic hydrocarbyl group, which can be saturated or partiallyunsaturated. Preferred alkyl groups are normal, branched and cyclicC₁-C₈-alkyl and -alkenyl groups.

In another embodiment, the NGF/p75^(NTR) binding inhibitor of Formula 3

where D₁, D₂, X₁, X₂, Y, E₁, E₂, T₁, T₂, R, G, R₁, R₂, and c have themeanings given above for these variables in Formula 1. Y₁, Y₂, and Y₃are independently selected from the identities liven for Y in Formula 1.E₃ and E₄ are each, independently, an sp²-hybridized carbon or nitrogenatom, and d and h are each, independently, 0 or 1.

In one embodiment of the compounds of Formula 3, R₁ is a mono- orpolycyclic aryl or heteroaryl, oligo- or monosaccharide group which issubstituted with at least one electronegative atom or electronegativegroup. The mono- or polycyclic aryl or heteroaryl group is preferablysubstituted with an acid functional group, such as —CO₂H; —SO₃H; —SO₂H;—PO₃H₂; —OSO₃H; HOC(O)-alkyl; HOS(O)₂-alkyl; HOS(O)-alkyl;(OH)₂P(O)-alkyl; and HOS(O)₂O-alkyl; where the alkyl group is preferablya C₁-C₄-alkyl group. In another embodiment, the electronegative atom orelectronegative functional group is selected from the group consistingof alkylcarbonyl; alkylthiocarbonyl; alkoxycarbonyl: —CN; —NO₂; —ONO₂,—CNO, —SH, —CNS, nitroalkyl, N,N-dialkylaminosulfonyl, aminocarbonyl,alkoxycarbonyl, alkoxycarbonylalkyl, cyanocarbonylalkyl, fluoromethyl,difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl,trichloromethyl, acetamido and halogen atoms. R₁ can also be analkylamino, alkyl or alkoxy group which is substituted with at least oneelectronegative atom or functional group. For example, in oneembodiment, R₁ is selected from the group consisting of —(CH₂)_(a)NO₂;—(CH₂)_(a)OH; —(CH₂)_(a)PO₃H₂; —(CH₂)_(a)SO₃H; —(CH₂)_(a)SO₂H;—O(CH₂)_(a)COOH; —O(CH₂)_(a)NO₂; —O(CH₂)_(a)PO₃H₂; —O(CH₂)_(a)SO₂H;—O(CH₂)_(a)SO₃H; —O(CH₂)_(a)OH; —NH(CH₂)_(a)COOH; —NH(CH₂)_(a)NO₂;—NH(CH₂)_(a)PO₃H₂; —NH(CH₂)_(a)SO₂H; and NH(CH₂)_(a)SO₃H; where a is 1to 12, preferably 1 to about 4.

In another embodiment of the compounds of Formula 3, R₁ is a phenylgroup which is substituted by p-toluenesulfonamido or hydroxyl; or R₁ isa —NH(CH₂)_(a)OH group, where a is 1 to about 4; a carboxyalkyl group,for example, a linear or branched carboxy-C₁-C₈-alkyl group; analkoxycarbonyl group, such as a linear or branched C₁-C₈-alkoxycarbonylgroup or an alkylcarbonate group, such as a linear or branchedC₁-C₈-alkylcarbonate group. In this embodiment, ring atom is ansp2-hybridized carbon atom, except for G, which is a nitrogen atom; Rand R₂ are both O; and d, c and h are each 1.

Preferred compounds of Formula 3 are of the formula

where X and R₁ have the meanings given above for these variables inFormula 1, R₂ is O, CH, or NR₃, where R₃ is H, alkyl, preferablyC₁-C₆-alkyl or aryl and ring 1 and 4 can, optionally independently befurther substituted. Suitable substituents include alkyl groups,preferably normal or branched C₁-C₆-alkyl groups.

In another embodiment, the NGF/p75^(NTR) binding inhibitor is of Formula2.

In Formula 2, D₁, D₂, E₁, E₂, E₃, E₄ and G are each, independently, ansp²-hybridized carbon or nitrogen atom. One of X₁ and X₂ is a hydrogenatom or absent, while the other is an electronegative atom or anelectronegative functional group. R, R₂ and R₄ are each, independently,an electronegative atom or an electronegative functional group, such asO, S, CH₂, or NR₃, where R₃ is H, alkyl, preferably C₁-C₆-alkyl, oraryl, such as phenyl. R, R₂ and one of X₁ and X₂ can also each be,independently, an electronegative atom or functional group, such asalkylcarbonyl; alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH;—CN; —CO₂H; —SO₃H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H,—OC(O)(OH); halomethyl, dihalomethyl or trihalomethyl group or afluorine, chlorine, bromine or iodine atom. Y is N, O, S, C-L or N-L,where L is H, alkyl, preferably C₁-C₆-alkyl, or an electronegative atomor functional group, such as, but not limited to, alkylcarbonyl;alkylthiocarbonyl; alkoxycarbonyl; aminocarbonyl; —OH; —CN; —CO₂H;—SO₂H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO, —SH, —CNS, —OSO₃H, —OC(O)(OH);halomethyl, dihalomethyl or trihalomethyl groups or a halogen atom, suchas a fluorine, chlorine, bromine or iodine atom. Z and Z₁ are each,independently, O, S, CH, C═O, N, NH, N-alkyl, N-cycloalkyl and N—P,where P is a carbohydrate moiety, such as a monosaccharide group, forexample, a fucosyl, glucosyl, galactosyl, mannosyl, fructosyl, gulosyl,idosyl, talosyl, allosyl, altrosyl, ribosyl, arabinosyl, xylosyl orlyxosyl group. T₁, T₂ and T₃ are each, independently, an sp²- orsp³-hybridized carbon or nitrogen atom. When f is 0, T₃ can further havethe meanings given for Z and Z₁, above, a, b, c, d, e, f and i are each0 or 1, provided that at least one of b and c is 1; at least one of dand e is 1 and at least one of f and i is 1.

R₁ is a monocyclic or polycyclic aryl or heteroaryl, oligo- ormonosaccharide, alkyl, cycloalkyl, arylalkyl alkylamino or alkoxy groupwhich is substituted with at least one substituent selected from thegroup consisting of electronegative atoms and electronegative functionalgroups. Preferred monosaccharide groups include fucosyl, glucosyl,galactosyl, mannosyl, fructosyl, gulosyl, idosyl, talosyl, allosyl,altrosyl, ribosyl, arabinosyl, xylosyl and lyxosyl groups. Theelectronegative substituent can be bonded to the aryl or heteroaryl ringsystem, or monosaccharide group either directly or indirectly via abridging group, for example, an alkylene group such as a C₁-C₄-alkylenegroup or an oxyalkylene group. Suitable directly bonded and alkylenebridged electronegative atoms and functional groups include, but are notlimited to, alkylcarbonyl; alkylthiocarbonyl: alkoxycarbonyl;aminocarbonyl; —OH; —CN; —CO₂H; —SO₃H; —SO₂H; —PO₃H₂; —NO₂; —ONO₂, —CNO,—SH, —CNS, —OSO₃H; —OC(O)(OH); carboxyalkyl, nitroalkyl,N,N-dialkylaminosulfonyl, aminocarbonyl, alkoxycarbonyl,alkoxycarbonylalkyl, cyanocarbonylalkyl, haloalkyl, such asfluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl,dichloromethyl or trichloromethyl; alkyamido or a halogen atom, such asa fluorine, chlorine, bromine or iodine atom. In one embodiment, R₁ isselected from the group consisting of groups including, but not limitedto, —(CH₂)₂COOH; —(CH₂)_(a)NO₂; —(CH₂)_(a)OH; —(CH₁)_(a)PO₃H₂;—(CH₂)_(a)SO₃H; —(CH₂)_(a)SO₃H; —R₄(CH₂)_(a)COOH; —R₄(CH₂)_(a)NO₂;—R₄(CH₂)_(a)PO₃H₂; —R₄(CH₂)_(a)SO₂H; —R₄(CH₂)_(a)SO₃H; and—R₄(CH₂)_(a)OH, where a is 1 to 12, preferably 1 to about 4, and R₄ isNH or O.

Rings 1, 2 and 3 are each, independently, a five- or six-membered ringand, preferably, are each planar.

In another embodiment, the compound is of Formula 5,

wherein D₁, D₂, X₁, X₂, E₁, E₂, E₃, T₁, T₂, T₃, Z, G, R, R₁, R₂, R₄, b,c, e, f and i have the meanings given for these variables in Formula 2.Y₁, Y₂, and Y₃ are independently selected from the identities given forY in Formula 2, and g and h are each, independently, 0 or 1. E₅ and E₆are each, independently, an sp²-hybridized carbon or nitrogen atom, andg is 0 or 1. Ring 4 can be further unsubstituted or substituted with oneor more substituents, such as alkyl or aryl groups.

In one embodiment of the compounds of Formulas 1, 2, 3 and 5, R₁ isselected from the group consisting of substituted phenylene,naphthylene, quinolylene and other substituted aromatic andheteroaromatic groups. R₁, can also be a substituted ethynyl orpoly(ethynyl) group. Suitable identities for R₁ include, but are notlimited to, the groups shown below.

In each of these groups, J can be any of the electronegative atoms orgroups described in the definition of R₁ in Formulas 1 and 2.Preferably, J is selected from the group consisting of —OH, —CN—, —NO,—CO₂H, —SO₃H, —SO₂H, —F, —Cl, —B, —I, —PO₃H₂, —CF₃, —SO₂N(CH₃)₂,—C(O)NH₂, —C(O)CH₃, —C(O)OCH₃, —C(O)CN, —CH₂F, —CH₂Cl, —CF₂H, —CCl₂H,—CCl₃ and —NHC(O)CH₃; R₄ is NH or O, and n is an integer from 0 to about6.

Preferred compounds of Formula 1 are represented by Formulas 6-14,16-18, 21-30 and 32-34, below. Preferred compounds of Formula 3 arerepresented by Formulas 15, 19, 20 and 31 below.

In each of Formulas 6-34, R₁, X and Y have the meanings given above forthese variables in Formula 1. In Formulas 6, and 9-15, Z is selectedfrom the group consisting of O, S, NH, N-alkyl, N-cycloalkyl and N—P,wherein P is a carbohydrate moiety, preferably a monosaccharide moiety,such as a fucosyl, glucosyl, galactosyl, mannosyl, fructosyl, gulosyl,idosyl, talosyl, allosyl, altrosyl, ribosyl, arabinosyl, xylosyl orlyxosyl group. In Formulas 6, 7, 9, 10 and 12-17, R₂ is selected fromthe group consisting of O, S, CH, and NR₃, wherein R₃ is H, OH, aryl oralkyl.

Preferred compounds of Formulas 2 and 5 are of Formulas 35-49 below.

In Formulas 32-46, the structural variables X, R₁, R₂, Z and Y each havethe identities given previously for Formula 2.

In another embodiment, the NGF/p75^(NTR) binding inhibitor is of generalformula 50.

In Formula 50, the structural variables D₁, D₂, X₁, X₂, E₁, E₂, E₃, T₁,T₂, T₃, Z, G, R, R₁, R₂, R₄, b, and c have the meanings given for thesevariables in Formula 2. T₃ is an sp²- or sp³-hybridized carbon ornitrogen atom, and is preferably an sp²-hybridized carbon or nitrogenatom.

A preferred subset of compounds of Formula 3 is represented by Formula51,

In Formula 51, X, Y and R₁ each have the meanings given for thesevariables in Formula 1. R₂ is O, S, CH, or N—R₃, wherein R₃ is H, OH,alkyl, preferably normal or branched C₁-C₆-alkyl, or aryl, such asphenyl or substituted phenyl.

In a preferred embodiment, the NGF/p75^(NTR) inhibitor exhibits greaterNGF/p75^(NTR) binding inhibition in cells which express p75^(NTR) butnot trkA than in cells which express both p75^(NTR) and trkA. Thebinding of NGF to p75^(NTR) in cells which do not express trkA can,under certain conditions, mediate apoptotic cell death. The p75^(NTR)receptor has a greater affinity for NGF in this proapoptotic state, thatis, in cells which do not express triad. Compounds which exhibit greaterNGF/p75^(NTR) binding inhibitor in the absence of trkA advantageouslyselectively inhibit or interfere with processes such as apoptotic celldeath, while having a smaller effect on other p75^(NTR)-mediatedprocesses.

Preferred compounds which selectively inhibit the binding of NGF top75^(NTR) in cells which do not express trkA include compounds ofFormulas 52 and 53, below.

In Formulas 52 and 53, Q is selected from the group consisting ofC₁-C₅-alkylene; para- and meta-phenylene; cycloalkylene, carbohydrateand para- and meta-CH₂C₆H₂—. In Formulas 51 and 52, R₅, R₆ and R₇ are,preferably, each, independently, H, —COOH or —NO₂. More preferably, twoof R₅, R₆ and R₇ are H and the other is —COOH or —NO₂.

The present invention also relates to a method of inhibiting the bindingof NGF to p75^(NTR). The method comprises contacting NGF in the presenceof p75^(NTR) with an NGF/p75^(NTR) binding inhibitor, amount of aNGF/p75^(NTR) inhibitor compound, thereby, inhibiting binding of NGF top75^(NTR). The method can be practiced in vitro, for example, in a cellculture screening assay to screen compounds which potentially bind,activate or inhibit receptor function. In such a method, the inhibitorcompound can function by binding and eliminating any competing functionof NGF in the sample or culture. The inhibitor compounds can also beused to control NGF activity in neuronal cell culture. The method canalso be practiced in vivo, for example, to inhibit one or more processesmediated by binding of NGF to p75^(NTR).

In another embodiment, the invention provides a method of treating acondition mediated by NGF/p75^(NTR) binding in a patient. The methodcomprises the step of administering to the patient a therapeuticallyeffective amount of a NGF/p75^(NTR) binding inhibitor, such as any ofthe inhibitors described above. The condition to be treated can be anycondition which is mediated, at least in part, by binding of NGF to thep75^(NTR) receptor. Such conditions include, but are not limited to,Alzheimer's disease, epilepsy, pain, multiple sclerosis, amyotrophiclateral sclerosis, stroke and cerebral ischemia.

Preferably, the NGF/p75^(NTR) binding inhibitor to be administeredselectively inhibits the binding of NGF to p75^(NTR) in cells which donot express trkA. In this embodiment, the condition is mediated, atleast in part, by the binding of NGF to the p75^(NTR) receptor in cellswhich do not express the trkA receptor. Generally, such conditions aremediated by NGF-induced apoptotic cell death.

The quantity of a given compound to be administered will be determinedon an individual basis and will be determined, at least in part, byconsideration of the individual's size, the severity of symptoms to betreated and the result sought. The NGF/p75^(NTR) binding inhibitor canbe administered alone or in a pharmaceutical composition comprising theinhibitor, an acceptable carrier or diluent and, optionally, one or moreadditional drugs.

The NGF/p75^(NTR) binding inhibitor can be administered subcutaneously,intravenously, parenterally, intraperitoneally, intradermally,intramuscularly, topically, enteral (e.g., orally), rectally, nasally,buccally, sublingually, vaginally, by inhalation spray, by drug pump orvia an implanted reservoir in dosage formulations containingconventional non-toxic, physiologically acceptable carriers or vehicles.The preferred method of administration is by oral delivery. The form inwhich it is administered (e.g., syrup, elixir, capsule, tablet,solution, foams, emulsion, gel, sol) will depend in part on the route bywhich it is administered. For example, for mucosal (e.g., oral mucosa,rectal, intestinal mucosa, bronchial mucosa) administration, nose drops,aerosols, inhalants, nebulizers, eye drops or suppositories can be used.The compounds and agents of this invention can be administered togetherwith other biologically active agents, such as analgesics,anti-inflammatory, agents, anesthetics and other agents which cancontrol one or more symptoms or causes of a p75^(NTR)-mediatedcondition.

In a specific embodiment, it may be desirable to administer the agentsof the invention locally to a localized area in need of treatment; thismay be achieved by, for example, and not by way of limitation, localinfusion during surgery, topical application, transdermal patches, byinjection, by means of a catheter, by means of a suppository, or bymeans of an implant, said implant being of a porous, non-porous, orgelatinous material, including membranes, such as sialastic membranes orfibers. For example, the agent can be injected into the joints.

The compound of the invention can, optionally, be administered incombination with one or more additional drugs which, for example, areknown for treating and/or alleviating symptoms of the condition mediatedby p75^(NTR) The additional drug can be administered simultaneously withthe compound of the invention, or sequentially.

The present invention also provides pharmaceutical compositions. Suchcompositions comprise a therapeutically (or prophylactically) effectiveamount of one or more NGF/p75^(NTR) binding inhibitors, preferably oneor more compounds of Formulas 1, 2, 4 or 5, as described above, and apharmaceutically acceptable carrier or excipient. Suitablepharmaceutically acceptable carriers include, but are not limited to,saline, buffered saline, dextrose, water, glycerol, ethanol, andcombinations thereof. The carrier and composition can be sterile. Theformulation should suit the mode of administration.

Suitable pharmaceutically acceptable carriers include but are notlimited to water, salt solutions (e.g., NaCl), alcohols, gum arabic,vegetable oils, benzyl alcohols, polyethylene glycols, gelatin,carbohydrates such as lactose, amylose or starch, cyclodextrin,magnesium stearate, talc, silicic acid, viscous paraffin, perfume oil,fatty acid esters, hydroxymethylcellulose, polyvinyl pyrolidone, etc.The pharmaceutical preparations can be sterilized and if desired, mixedwith auxiliary agents, e.g., lubricants, preservatives, stabilizers,wetting agents, emulsifiers, salts for influencing osmotic pressure,buffers, coloring, flavoring and/or aromatic substances and the likewhich do not deleteriously react with the active compounds.

The composition, if desired, can also contain minor amounts of wettingor emulsifying agents, or pH buffering agents. The composition can be aliquid solution, suspension, emulsion, tablet, pill, capsule, sustainedrelease formulation, or powder. The composition can be formulated as asuppository, with traditional binders and carriers such astriglycerides. Oral formulation can include standard carriers such aspharmaceutical grades of mannitol, lactose, starch, magnesium stearate,polyvinyl pyrollidone, sodium saccharine, cellulose, magnesiumcarbonate, etc.

The composition can be formulated in accordance with the routineprocedures as a pharmaceutical composition adapted for intravenousadministration to human beings. Typically, compositions for intravenousadministration are solutions in sterile isotonic aqueous buffer. Wherenecessary, the composition may also include a solubilizing agent and alocal anesthetic to ease pain at the site of the injection. Generally,the ingredients are supplied either separately or mixed together in unitdosage form, for example, as a dry lyophilized powder or water freeconcentrate in a hermetically sealed container such as an ampule orsachet indicating the quantity of active agent. Where the composition isto be administered by infusion, it can be dispensed with an infusionbottle containing sterile pharmaceutical grade water, saline ordextrose/water. Where the composition is administered by injection, anampule of sterile water for injection or saline can be provided so thatthe ingredients may be mixed prior to administration.

The pharmaceutical compositions of the invention can also include anagent which controls release of the NGF/p75^(NTR) inhibitor compound,thereby providing a timed or sustained release composition.

The present invention also relates to prodrugs of the NGF/p75^(NTR)binding inhibitors disclosed herein, as well as pharmaceuticalcompositions comprising such prodrugs. For example, compounds of theinvention which include acid functional groups or hydroxyl groups canalso be prepared and administered as a corresponding ester with asuitable alcohol or acid. The ester can then be cleaved by endogenousenzymes within the patient to produce the active agent.

In a further embodiment, the invention relates to the use of anNGF/p75^(NTR) binding inhibitor, such as any of the compounds describedabove, for treating a condition mediated by binding of NGF to p75^(NTR).The invention further relates to the use of these compounds for themanufacture of a medicament for treating a condition mediated by bindingof NGF to p75^(NTR).

Representative syntheses of compounds of the invention are set forth inthe following examples. Other synthetic pathways that can be used toprepare certain compounds of the invention are illustrated in FIGS. 3and 4.

EXAMPLES Example 1 Synthesis of NGF/p75^(NTR) Inhibitors General Methods

Reagents and solvents were obtained from commercial sources (Sigma,Aldrich, BDH). THF was dried by refluxing with benzophenone andpotassium and subsequently distilled. All other solvents were utilizedas they were received.

Thin layer chromatography (TLC) solvent systems used are given inTable 1. These were developed by ascending TLC on precoated aluminumbacked sheets of silica gel 60 F254 (Merck). TLC plates were developedusing ultra-violet light, iodine crystal and/or ninhydrin.

Melting points (mp) were determined on a Thomas Hoover Unimelt meltingpoint apparatus and are uncorrected.

NMR of final compounds were determined on an AVANCE 300 MHz NURspectrometer. All NMR samples were prepared in DMSO-d6 unless otherwiseindicated. Chemical shifts are reported as δ parts per million usingDMSO as an internal reference. Mass spectrometric (MS) analyses wereobtained on a Varian Instrument VG Quattro multiple quadripolespectrometer using electrospray ionization (ESI). The spectra were allobtained in the negative ion mode. IR spectra were recorded on a BomenMB-E120 FT-IR spectrophotometer.

Abbreviations used herein are: HOAc, glacial acetic acid; THF,tetrahydrofuran; DMSO-d₆, deuterated dimethylsulfoxide; CHCl₃,chloroform: MeCN, acetonitrile; H₂O, distilled water; MeOH, methanol;EtOH, ethanol; TEA, triethylamine; EtOAc, ethyl acetate.

TABLE 1 List of Solvent Systems. Solvent Code Solvent System SolventRatio A MeOH:HOAc  5:1 B MeCN:H₂O:MeOH  8:1:1 C MeCN:H₂O:MeOH  4:1:1 DCHCl₃:MeOH:HOAc 95:10:3 E EtOH:HOAc 50:1

General Synthesis of Naphthalimide Derivatives

Method A. The naphthalimide series of compounds was prepared through thecondensation of stoichiometric amounts of 1,8-naphthalic anhydride orits derivative (I) with an appropriate primary amine (II). The combinedreagents were dissolved in glacial acetic acid, dry THF, dry 1,4-dioxaneor DMSO and placed under a N₂ atmosphere and refluxed. The progress ofthe reaction was monitored by TLC. Final clear solutions wereconcentrated in vacuo and the resulting crude material was eitherreprecipitated from 1,4-dioxane/1N HCl or HOAc/H₂O and/or recrystallizedfrom 95% ethanol, THF or 1,4-dioxane. In the instances where the finalproduct precipitated out of the reaction solution, the completedreaction mixture was cooled to room temperature, the solid collected byfiltration and washed with distilled water. This precipitate wasreprecipitated with 1,4-dioxane, 1N HCl or HOAc/H₂O and/orrecrystallized from 95% ethanol, THF or 1,4-dioxane. Purification alsoincluded fractional recrystallisation.

where X and R₁ are as previously defined.

Method B. Reaction conditions and purification procedures were similarto those of method A. However, instead of stoichiometric amounts ofreagents, the anhydride (I) and the primary amine(II) were combined in a1:2 ratio with the optional addition of 1 equivalent of anhydrous sodiumacetate. During the course of preparing the various naphthalimidederivatives, these reaction conditions were found to lead to increasedproduct yields. Glacial acetic acid was the solvent of choice used underthese conditions.

TABLE 2 Synthesized Naphthalimide Derivatives

Compd. X R₁ Name 200 3-NO₂ CH₂COOH N-(1-carboxymethyl)-3-nitro-1,8-naphthalimide; 2-(1-carboxymethyl)- 5-nitrobenzo[d,e]isoquinoline-1,3-dione 201 3-NO₂ CH₂CH₂COOH N-(2-carboxymethyl)-3-nitro-1,8-naphthalimide; 2-(2-carboxymethyl)-5-nitrobenzo[d,e]isoquinoline-1,3-dione 202 3-NO₂ CH₂(CH₂)₂COOHN-(3-carboxypropyl)-3-nitro-1,8- naphthalimide; 2-(3-carboxypropyl)-5-nitrobenzo[d,e]isoquinoline-1,3- dione 203 3-NO₂ CH₂(CH₂)₃COOHN-(4-carboxybutyl)-3-nitro-1,8- naphthalimide; 2-(4-carboxybutyl)-5-nitrobenzo[d,e]isoquinoline-1,3-dione 204 3-NO₂ CH₂(CH₂)₄COOHN-(5-carboxypentyl)-3-nitro-1,8- naphthalimide; 2-(5-carboxypentyl)-5-nitrobenzo[d,e]isoquinoline-1,3-dione 220 4-NO₂ CH₂COOHN-(1-carboxymethyl)-4-nitro-1,8- naphthalimide; 2-(1-carboxymethyl)-6-nitrobenzo[d,e]isoquinoline-1,3- dione 221 4-NO₂ CH₂CH₂COOHN-(2-carboxyethyl)-4-nitro-1,8- naphthalimide; 2-(2-carboxyethyl)-6-nitrobenzo[d,e]isoquinoline-1,3-dione 222 4-NO₂ CH₂(CH₂)₂COOHN-(3-carboxypropyl)-4-nitro-1,8- naphthalimide; 2-(3-carboxypropyl)-6-nitrobenzo[d,e]isoquinoline-1,3- dione 223 4-NO₂ CH₂(CH₂)₃COOHN-(4-carboxybutyl)-4-nitro-1,8- naphthalimide; 2-(4-carboxybutyl)-6-nitrobenzo[d,e]isoquinoline-1,3-dione 224 4-NO₂ CH₂(CH₂)₄COOHN-(5-carboxypentyl)-4-nitro-1,8- naphthalimide; 2-(5-carboxypentyl)-6-nitrobenzo[d,e]isoquinoline-1,3-dione

Naphthalimide Derivatives: Method A:N-(1-carboxymethyl)-3-nitro-1,8-naphthalimide (200)

3-nitro-1,8-naphthalic anhydride (1.0 g, 0.0041 mol) and glycine (0.31g, 0.0041 mol) and 50-60 mls of glacial acetic acid were added to a 100ml round-bottom flask equipped with a reflux condenser, heating mantleand stir plate. The system was placed under a N₂ atmosphere and heatedto a gentle reflux. The progress of the reaction was monitored by TLC.After four days, the clear dark amber solution was concentrated undervacuum and the crude brown material reprecipitated with 1,4-dioxane/1NHCl. The precipitate was filtered through a Buchner funnel and washedwith water. Successive fractional recrystallizations in ethanol afforded0.35 g (28%) of 200 as a beige powder: M. Pt. 260-262° C.; TLC R_(f)0.83 (A): R_(f) 0.82 (B): R_(f) 0.23 (D): ¹H NMR (DMSO-d₆); IR (cm⁻¹):2750-3100 (OH), 3077 (C═CH), 2665 (C—H), 1732 (C═O), 1711 (bs, C═O),1670 (C═O), 1597 (C═C), 1538 (N═O), 1509 (C═C), 1430 (C═C), 1372 (C—O),1341 (N—O), 1244 (C—O), 787 (C═CH). MS m/z (rel intensity) 299 (97) 255(100), 281 (93), 172 (26).

N-(2-carboxyethyl)-3-nitro-1,8-naphthalimide (201)

3-nitro-1,8-naphthalic anhydride (1.0 g, 0.0041 mol) and β-alanine(0.37, 0.0041 mol) were refluxed as per 200 for 48 hours. Precipitatethat formed during the course on the reaction was filtered and washedwith water. The filtrate was concentrated under vacuum and the crudebrown material reprecipitated with 1,4-dioxane/1N HCl. The precipitatewas filtered through a Buchner funnel and washed with water. Both solidswere combined and triturated with hot ethanol and 1,4-dioxane. Anyundissolved material was removed by filtration. The combined ethanol and1,4-dioxane fractions were concentrated in vacuo. Crystallization fromethanol afforded 0.38 g (30%) of 201 as a beige powder: M. Pt. 246-248°C.; TLC R_(f) 0.74 (A): R_(f) 0.84 (B): R_(f) 0.67 (D): ¹H NMR(DMSO-d₆); IR (cm⁻¹): 2800-3130 (OH), 3071 (C═CH), 2646 (C—H), 1707 (bs,C═O), 1663 (C═O), 1625 (C═C), 1597 (C═C), 1537 (NMO), 1439 (C═C), 1420(C═C). 1369 (C—O), 1347 (N—O), 1243 (C—O), 789 (C═CH). MS m/z (relintensity) 313 (100) 241 (42).

N-(3-carboxypropyl)-3-nitro-1,8-naphthalimide (202)

3-nitro-1,8-naphthalic anhydride (1.0 g, 0.0041 mol) and 4-aminobutyricacid (0.42 g. 0.0041 mol) were refluxed as per 200 for 48 hours.Resultant solution was purified as per 201 to afford 0.55 g (42%) of 202as a fluffy beige solid: M. Pt. 200-202° C.; TLC R_(f) 0.88 (A): R_(f)0.85 (B): R_(f) 0.75 (D): ¹H NMR (DMSO-d₆); IR (cm⁻¹): 2875-3100 (OH),3062 (C═CH), 2560 (C—H), 1785 (C═O), 1702 (C═O), 1658 (C═O), 1625 (C═C),1595 (C═C), 1538 (N═O), 1438 (C═C), 1418 (C═C), 1372 (C—O), 1334 (N—O),1244 (C—O), 789 (C═CH). MS m/z (rel intensity) 327 (100) 241 (40).

N-(4-carboxybutyl)-3-nitro-1,8-naphthalimide (203)

3-nitro-1,8-naphthalic anhydride (0.5 g, 0.0020 mol) and5-aminopentanoic acid (0.24 g, 0.0020 mol) were refluxed in DMSO as per200 for 24 hours. The dark orange brown solution was diluted with wateruntil a beige precipitate formed. The precipitate was filtered through aBuchner funnel and washed copiously with water. The process was repeatedon the concentrated filtrate. Combined solids were recrystallized in1,4-dioxane/1N HCl. The filtered product was dried in air for a shorttime and then in vacuo for 48-72 hours to afford 0.43 g (63%) 203 as abeige feathery solid: M. Pt. 2033-205° C.: TLC R_(f) 0.92 (A): R_(f)0.89 (C); R_(f) 0.26 (D): ¹H NMR (DMSO-d₆); IR (cm⁻¹): 2700-3130 (OH),3066 (C═CH), 1784 (C═O), 1706 (bs, C═O), 1659 (C═C), 1625 (C═C), 1596(C═C), 1541 (N═C), 1458 (C═C), 1438 (C═C), 1351 (N—O), 1245 (C—O), 789(C═CH). MS m/z (rel intensity) 341 (100), 241 (16), 216 (24).

N-(5-carboxypentyl)-3-nitro-1,8-naphthalimide (204)

3-nitro-1,8-naphthalic anhydride (1.0 g, 0.0041 mol) and 6-aminohexanoicacid (0.54 g, 0.0041 mol) were refluxed in 100 ml THF and 10 ml DMSO asper 200 for 24 hours. The dark-brown solution was concentrated andmanipulated as per 203 to yield 1.0 g (67%) 204 as beige powder: M. Pt.192-194° C.; TLC R_(f) 0.70 (A): R_(f) 0.91 (B): R_(f) 0.63 (D): ¹H NMR(DMSO-d₆) δ 1.36 (m, 2H), 1.54 (m, 2H), 1.64 (m. 2H), 2.22 (t. J=7.3 Hz.2H), 4.02 (t. J=7.3 Hz, 2H), 8.02 (dd, J=7.1, 8.3 Hz, 1H), 8.63 (d,J=7.1 Hz. 1H), 8.73 (d, J=8.3 Hz, 1 Hz), 8.89 (d, J=2.3 Hz, 1H), 9.43(d, J=2.3 Hz, 1H); IR (cm⁻¹): 2700-3175 (OH), 3075 (C═CH), 2688 (C—H),1706 (bs, C═O), 1663 (C═O), 1625 (C═C), 1598 (C═C), 1533 (N═O), 1437(C═C), 1419 (C═C), 1348 (N—O), 1244 (C—O), 791 (C═CH). MS m/z (relintensity) 355 (100).

N-(2-carboxyethyl)-4-nitro-1,8-naphthalimide (221)

4-nitro-1,8-naphthalic anhydride (0.5 g, 0.0020 mol) and β-alanine (0.18g, 0.0020 mol) were refluxed for 4 days and the final mixture purifiedas per 200. Successive fractional recrystallisations in CHCl₃ afforded0.24 g (38%) 221 as an beige solid: M. Pt. 224-225° C.; TLC R_(f) 0.77(A): R_(f) 0.80 (C): R_(f) 0.46 (D): ¹NMR (DMSO-d₆); IR (cm⁻¹):2800-3175 (OH), 3077 (C═CH), 2637 (C—H), 1788 (C═O), 1705 (bs, C═O),1657 (C═C), 1624 (C═C), 1594 (C═C), 1534 (N═O), 1440 (C═C), 1408 (C═C),1346 (N—O), 1229 (C—C), 789 (C═CH). MS m/z (rel intensity) 314 (16), 313(100). 274 (50).

N-(3-carboxypropyl)-4-nitro-1,8-naphthalimide (222)

4-nitro-1,8-naphthalic anhydride (0.5 g, 0.0020 mol) and 4-aminobutyricacid (0.21 g. 0.0020 mol) were refluxed for 5 days in dry THF as per200. The dark orange amber solution was concentrated to 20 ml in vacuoand diluted with 1N HCl until a beige precipitate formed. Theprecipitate was filtered through a Buchner funnel and washed with water.The crude material was reprecipitated from 1,4-dioxane, 1N HCl andfiltered. Successive fractional recrystallisations in CHCl₃ afforded0.22 g (34%) of 222 as a beige solid: M. Pt. 179-180° C.; R_(f) 0.85(A): TLC R_(f) 0.81 (B): R_(f) 0.48 (D): ¹H NMR (DMSO-d₆); IR (cm⁻¹):2780-3200 (OH). 3075 (C═CH), 2688 (C—H). 1778 (C═O), 1705 (bs, C═O),1655 (C═O), 1624 (C═C), 1584 (C═C), 1534 (N═O). 1439 (C═C), 1409 (C═C),1344 (N—O), 1231 (C—O), 789 (C═CH). MS m/z (rel intensity) 328 (20), 327(100), 274 (27), 241 (36).

N-(4-carboxybutyl)-4-nitro-1,8-naphthalimide (223)

4-nitro-1,8-naphthalic anhydride (0.5 g, 0.0020 mol) and5-aminopentanoic acid (0.24 g, 0.0020 mol) were refluxed for 3 days indry THF as per 200. The dark orange amber solution was purified as per222 to afford 0.27 g (40%) of 223 as a orange powder: M. Pt. 198-200°C.; TLC R_(f) 0.84 (A): R_(f) 0.88 (C): R_(f) 0.46 (D): ¹H NMR(DMSO-d₆). IR (cm⁻¹): 2825-3130 (OH), 3077 (C═CH), 2670 (C—H). 1704 (bs,C═O). 1660 (C═O), 1624 (C═C), 1583 (C═C), 1529 (N═O), 1435 (C═C), 1411(C═C). 1345 (N—C), 1233 (C—C), 787 (C═CH). MS m/z (rel intensity) 342(19), 341 (100), 274 (20). 241 (40).

N-(5-carboxypentyl)-4-nitro-1,8-naphthalimide (224)

4-nitro-1,8-naphthalic anhydride (0.5 g, 0.0020 mol) and 6-aminohexanoicacid (0.27 g, 0.0020 mol) were refluxed for 3 days in dry THF and thefinal mixture purified as per 223. Crystallization from THF/1N HClafforded 0.65 g (95%) of 224 as a beige solid: M. Pt. 168-169° C.; TLCR_(f) 0.85 (A): R_(f) 0.81 (B): R_(f) 0.50 (D): ¹H NMR (DMSO-d₆); IR(cm⁻¹): 2775-3175 (OH), 3078 (C═CH), 2670 (C—H), 1716 (bs, C═O), 1661(C═O), 1624 (C═C). 1594 (C═C). 11-21 (N═O), 1136 (C═C), 1409 (C═C), 339(N—O), 1261 (C—O). 785 (C═CH). MS m/z (rel intensity), 365 (21), 355(100).

Method B: N-(1-carboxymethyl)-4-nitro-1,8-naphthalimide (220)

4-nitro-1,8-naphthalic anhydride (1.0 g, 0.0041 mol), glycine (0.38 g,0.0082 mol), anhydrous sodium acetate (0.51 g, 0.61 mol) and 70-80 mlsof glacial acetic acid were added to a 100 ml round-bottom flaskequipped with a reflux condenser, heating mantle and stir plate. Thesystem was placed under a N₂ atmosphere and heated to a gentle reflux.After 3 days, the dark amber solution was concentrated to 15-20 ml undervacuum with a rotary evaporator. Ensuing precipitate was filtered andwashed twice with 5 ml 1N HCl and twice with 5 ml water. Crystallizationfrom 1,4-dioxane/H₂0 afforded 0.6 g (50%) 220 as a beige solid: M. Pt.263-264° C.; TLC R_(f) 0.81 (A): R_(f) 0.84 (C): R_(f) 0.35 (D): ¹H NMR(DMSO-d₆) δ 4.74 (s, 2H), 8.10 (dd, J=8.4, 8.0 Hz, 1H), 8.55 (d, J=7.6Hz, 1H), 8.63 (d, J=8.0 Hz, 1H), 8.65 (d, J=8.0, 1H), 8.73 (d, J=8.4 Hz.1H); IR (cm⁻¹): 2850-3150 (OH), 3077 (C═CH), 2671 (C—H), 1711 (C═O),1674 (bs, C═O), 1625 (C═C), 1583 (C═C), 1531 (N═O), 1429 (C═C), 1334(N—O), 1232 (C—O), 785 (C═CH). MS m/z (rel intensity) 299 (100), 255(280).

Example 2 Assessment of NGF/p75^(NTR) Binding Inhibition

The radio-iodination and receptor binding of NGF (Sutter et al., 1979)was performed with modifications (Ross et al., 1997) as follows:Evaluation of the ability of NCP compounds to inhibit TrkA and p75^(NTR)binding was determined by the binding of ¹²⁵I-NGF to PC12 cells (ratpheochromocytoma cells expressing TrkA and p75^(NTR); obtained fromATCC) and PC12^(nnr5) (rat pheochromocytoma cells expressing p75^(NTR)only; obtained from Dr. L. Greene, Columbia University, NY). Thep75^(NTR) is in a low affinity state and a high affinity state,respectively, in these cell types (Ross et al., 1998). PC12 andPC12^(nnr5) cells were grown in RPMI (Sigma) with 10% heat inactivateddonor horse serum and 5% fetal calf serum. Cells were harvested byreplacing the medium with calcium, magnesium-free balanced salt solution(Gey's solution) and incubating at 37° C. for 15 minutes. Cells werepelleted b centrifugation and suspended in HKR buffer (10 mM Hepes [pH7.35] containing 125 mM NaCl, 4.8 mM KCl, 1:3 mM CaCl₂, 1.2 mM MgSO₄,1.2 mM KH₂PO₄, 1 g/L glucose and 1 g/L BSA) at a cell concentration of2×10⁶/mL and kept at 4° C. Triplicate tubes were set up for totalbinding, non-specific binding and binding in the presence of candidatecompetitor molecule (i.e., a tube for each data point). Each tubecontained ¹²⁵I-NGF (at 1 nM), 400,000 cells (for a final cellconcentration of 10⁶/mL) and NGF (50 mM, to define non-specificbinding), as required. The tubes were incubated for 2 h at 4° C. andspecific binding evaluated by measuring specifically bound DPM (Ross etal., 1997). Data were analysed and the results expressed as receptorbinding observed in the presence of competitor as a percentage ofreceptor binding in the absence of a competitor.

TABLE 3 Results of in vitro binding inhibition assays PC12 nnr5 Compound(50 μM) % of Max % of Max 200 92, 87, 74 = 84 58, 63, 64 = 62 201 27,32, 41 = 33 30, 4, 34 = 23 202 21, 22, 30 = 24 16, 0, 0 = 5 203 36, 41,35 = 37 33, 0, 18 = 17 204 41, 41, 36 = 39 12, 0, 47 = 20 220 NS 37, 43,49 = 43 21, 17, 26 = 21 221 29, 32, 31 = 31 41, 37, 42 = 40 222 NS NT NT223 27, 33, 33 = 31 40, 41, 47 = 43 224 31, 34, 22 = 29 36, 35, 39 = 36NS: Not Soluble @ 100 μM DMSO NT: Not Tested

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various chances in form and details may bemade therein without departing from the spirit and scope of theinvention as defined by the appended claims.

REFERENCES CITED

-   Barbacid. Oncogene 8:2033-2042 (1993)-   Barde, Neuron 2:1525-1534 (1989)-   Barker and Shooter, Neuron 13:203-215 (1994)-   Ben Ari and Represa, TINS 13:312-318 (1990)-   Berkemeier et al., Neuron 7:857-866 (1991)-   Bothwell, Cell 65:915-918 (1991)-   Bothwell and Shooter, J. Biol. Chem. 3:8532-8536 (1977)-   Bradshaw et al. Protein Science 3:1901-1913 (1994)-   Burton et al. J. Neurochem. 59:1937-1945 (1992)-   Burton et al., Soc. Neurosci. Abs. 21:1061 (1995)-   Carter et al. Science 272:542-545 (1996)-   Cassacia-Bonnefil et al. Nature 383:716-719 (1996)-   Chao, Neuron 9:583-593 (1992b)-   Chao, J. Neurobiol. 25: 1373-1385 (1994)-   Chao and Hempstead, Trends Neurosci. 18:321-326 (1995)-   Dobrowsky et al., Science 265:1596-1599 (1994)-   Drinkwater et al., J. Biol. Chem. 268:23202-23207 (1993)-   Escandon et al., Neurosci. Res. 34:601-613 (1993)-   Gotz et al., Nature 372:266-269 (1994) Gregory et al. Protein    Engineering 6:29-35 (993)-   Hallböök et al., Neuron 6:845-858 (1991)-   Hefti, J. Neurosci. 6:2155-2162 (1986)-   Hefti and Weiner, Annals of Neurology 20:275-281 (1986)-   Heldin et al., J. Biol. Chem. 264:8905-8912 (1989)-   Hempstead et al., Nature 350:678-683 (1991)-   Herrmann et al., Mol. Biol. 4:1205-1216 (1993)-   Hohn et al., Nature 344:339-341 (190)-   Ibáñez et al., Cell 69:329-341 (1992)-   Ibáñez et al., EMBO J. 12:2281-2293 (1993)-   Ibáñez, Trends Biotech. 13:217-227 (1995)-   Jing et al., Neuron 9:1067-1079 (1992)-   Kahle et al., J. Biol. Chem. 267:22707-22710 (1992)-   Kaplan et al., Science 252:554-558 (1991)-   Klein et al., Cell 65:189-197 (1991)-   Klein et al., Neuron 8:947-956 (1992)-   Lamballe et al., Cell 66:967-970 (1991)-   Landreth and Shooter, Proc. Natl. Acad. Sci. U.S.A. 77:4751-4755    (1980)-   Leibrock et al., Nature 341:149-152 (1989)-   Leven and Mendel, TINS 16:353-359 (1993)-   Levi-Montalcini, EMBO J. 6:1145-1154 (1987)-   Luo and Neet, J. Biol. Chem. 267:12275-12283 (1992)-   Mahadeo et al., J. Biol. Chem. 269:6884-6891 (1994)-   Maisonpierre et al., Science 247:1446-1451 (1990)-   Maness et al., Neurosci. Biobehav. Rev. 18:143-159 (1994)-   Marchetti et al., Cancer Res. 56:2856-2863 (1996)-   Matsumoto et al., Cancer Res. 55:1798-1806 (1995)-   McDonald et al., Nature 354:411-414 (1991)-   McKee et al., Ann. Neurol. 30:156 (1991)-   McMahon et al. Nature Med. 1:774-780 (1995)-   Meakin and Shooter, Trends Neurosci. 15:323-331 (1992)-   Moore and Shooter, Neurobiology 5:369-381 (1975)-   Radziejewski et al. Biochemistry 31:4431-4436 (1992)-   Rashid et al., Proc. Natl. Acad. Sci. U.S.A. 92:9495-9499 (1995)-   Rodrigues-Tébar et al., Neuron 4:487-492 (1990)-   Rodrigues-Tébar et al., EMBO J. 11:917-922 (1992)-   Rosenthal et al., Neuron 4:767-773 (1990)-   Ross et al., J. Cell Biol. 132:945-953 (1996)-   Ross et al., Nature Med. 3:872-878 (1997)-   Ross et al. Eur. J. Neurosci. 10 890-898 (1998)-   Rydén and Ibáñez. J. Biol. Chem. 271:563-5627 (1996)-   Schechter and Bothwell. Cell 24:867-874 (1981)-   Shamovsky et al., Can. J. Chem. 76:1389-1401 (1998)-   Shamovsky et al. J. Am Chem. Soc 118:9743-9749 (1999)-   Shih et al., J. Biol. Chem. 269:27679-27686 (1994)-   Soppet et al., Cell 65:895-903 (1991)-   Squinto et al., Cell 65:885-893 (1991)-   Suter et al., J. Neurosci. 12:306-318 (1992)-   Sutter et al., J. Biol. Chem. 254:5972-5982 (1979)-   Taylor et al., Soc. Neurosci. Abs. 17:712 (1991)-   Treanor et al., J. Biol. Chem. 270:23104-23110 (1995)-   Vale and Shooter, Methods Enzymol. 109:21-39 (1985)-   Van der Zee et al. Science 274:1729-1732 (1996)-   Washiyama et al., Amer. J. Path. 148:929-940 (1996)-   Wolf et al., J. Biol. Chem. 270:2133-2138 (1995)-   Woolf and Doubell, Current Opinions in Neurobiol. 4:525-534 (1994)

1-42. (canceled)
 43. A compound having Formula 4:

or a pharmaceutically acceptable salt thereof; wherein X is NO₂; and R₁is CH₂(CH₂)₃COOH.
 44. The compound of claim 43, wherein the compoundhaving Formula 4 is N-(4-carboxybutyl)-3-nitro-1,8-naphthalimide orN-(4-carboxybutyl)-4-nitro-1,8-naphthalimide.
 45. The compoundN-(2-carboxyethyl)-4-nitro-1,8-naphthalimide.
 46. The compoundN-(3-carboxypropyl)-3-nitro-1,8-naphthalimide.
 47. A method of treatingAlzheimer's disease, epilepsy, multiple sclerosis, amyotrophic lateralsclerosis, stroke or pain in a patient, the method comprising the stepof administering to the patient a therapeutically effective amount of acompound having Formula 4:

or a pharmaceutically acceptable salt thereof; wherein X is 3-NO₂ or4-NO₂; and R₁ is CH₂(CH₂)₂COOH, or CH₂(CH₂)₃COOH.
 48. The method ofclaim 47, wherein X is 3-NO₂ or 4-NO₂.
 49. The method of claim 47,wherein the compound having Formula 4 isN-(3-carboxypropyl)-3-nitro-1,8-naphthalimide;N-(4-carboxybutyl)-3-nitro-1,8-naphthalimide;N-(3-carboxypropyl)-4-nitro-1,8-naphthalimide; orN-(4-carboxybutyl)-4-nitro-1,8-naphthalimide.
 50. The method of claim47, wherein the compound having Formula 4 isN-(3-carboxypropyl)-3-nitro-1,8-naphthalimide.
 51. A method of treatingAlzheimer's disease, epilepsy, multiple sclerosis, amyotrophic lateralsclerosis, stroke or pain in a patient, the method comprising the stepof administering to the patient a therapeutically effective amount ofN-(2-carboxyethyl)-4-nitro-1,8-naphthalimide.
 52. A method of inhibitingthe binding of nerve growth factor to the p75^(NTR) receptor, comprisingcontacting cells expressing the p75^(NTR) receptor with an effectiveinhibiting amount of a compound having Formula 4:

or a pharmaceutically acceptable salt thereof; wherein X is NO₂; and R₁is CH₂(CH₂)₂COOH, or CH₂(CH₂)₃COOH.
 53. The method of claim 52, whereinX is 3-NO₂ or 4-NO₂.
 54. The method of claim 52, wherein the compoundhaving Formula 4 is N-(3-carboxypropyl)-3-nitro-1,8-naphthalimide;N-(4-carboxybutyl)-3-nitro-1,8-naphthalimide;N-(3-carboxypropyl)-4-nitro-1,8-naphthalimide; orN-(4-carboxybutyl)-4-nitro-1,8-naphthalimide.
 55. The method of claim52, wherein the compound having Formula 4 isN-(3-carboxypropyl)-3-nitro-1,8-naphthalimide.
 56. A method ofinhibiting the binding of nerve growth factor to the p75^(NTR) receptor,comprising contacting cells expressing the p75^(NTR) receptor with aneffective inhibiting amountN-(2-carboxyethyl)-4-nitro-1,8-naphthalimide. Y, Y₁, Y₂, and Y₃ areeach, independently, N, O, S, C-L or N-L, where L is H, alkyl or anelectronegative atom or functional group; Z and Z₁ are each,independently, O, S, CH, C(O), N, NH, N-alkyl, N-cycloalkyl or N—P,where P is a carbohydrate moiety; T₁ and T₂ are each, independently, ansp²- or sp³-hybridized carbon or nitrogen atom; d, h and c are each 0 or1; and R₁ is a monocyclic or polycyclic aryl or heteroaryl group groupwhich is substituted with at least one substituent selected from thegroup consisting of hydroxyl and sulfonamide or an alkyl or alkylaminogroup substituted with a carboxyl or carbonate group; and at least onepharmaceutically acceptable carrier or excipient.